Move util_ files into utils directory, move main.cpp into src

[gssweb.git] / json_gssapi / src / utils / util_random.cpp

diff --git a/json_gssapi/src/utils/util_random.cpp b/json_gssapi/src/utils/util_random.cpp
new file mode 100644 (file)
index 0000000..2561629
--- /dev/null
+++ b/json_gssapi/src/utils/util_random.cpp
@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2014 <copyright holder> <email>
+ *
+ * For license details, see the LICENSE file in the root of this project.
+ *
+ */
+
+#include "util_random.h"
+
+#ifdef WIN32
+#include <random>
+#endif
+#ifdef HAVE_OPENSSL
+#include <openssl/err.h>
+#include <openssl/rand.h>
+#endif
+
+
+bool randGenPseudoRandom(unsigned char *buffer, size_t len)
+{
+#ifdef WIN32
+  std::random_device rd;   // slow; use to seed only!
+  std::mt19937 gen(rd());  // seed mersenne twister.
+  std::uniform_int_distribution<> dist(0,UCHAR_MAX);
+  for (size_t i=0; i<len; i++)
+    buffer[i] = dist(gen);
+  return true;
+#elif defined(HAVE_OPENSSL)
+  int  osslReturn = 0;
+  bool existingErrors = false;
+
+  /* Error checking */
+  // See if there are any queued OpenSSL errors already.
+  existingErrors = ( 0 == ERR_peek_error() );
+
+  /* Setup          */
+  /* Main           */
+  // Generate random byte string
+  osslReturn = RAND_pseudo_bytes(buffer, len);
+
+  // Discard the error message if there weren't any OpenSSL errors to begin with.
+  if (osslReturn == 1 && !existingErrors)
+  {
+    while (0 != ERR_get_error() );
+    return(false);
+  }
+  return true;
+#else
+  #error no pseudo random generator available
+#endif
+}
+